A wristwatch marketed by Jaeger Lecoultre under the reference “Master Grand Réveil” includes an alarm mechanism that automatically activates an alarm at a time predefined by the user. This alarm function is performed by a mechanism connected to the movement, which includes an independent barrel, a setting system for programming the strike time, an triggering system connected to the going train of the movement that activates the alarm at the set time, and a strike mechanism for alerting the user. The strike mechanism includes a gong, which is struck by a hammer to generate an acoustic signal, and also means for making the watch vibrate without generating an audible acoustic signal. A switch is used to select whether the acoustic alarm or silent vibrating alarm is activated.
This watch has drawbacks however. Indeed, the alarm mechanism includes specific elements enabling the mechanism to operate in silent alarm mode, which increases the complexity and size of the structure. Moreover, the vibration amplitude is limited.